science: how can DNA do so much?

Every time I’m in a doctor’s office and see an anatomical poster showing the shape of the bones in your ear, or the five layers of the cornea and the custom oil ducts that keep it lubricated, or the name for every bump and wiggle in your intestines, and realize the Adobe Illustrator file for that one structure is bigger than the entire DNA that built it and there are 500 more anatomical posters to go, I start banging my head on the wall.

How does less information than on a Britney Spears CD (3 billion base pairs each storing two bits of data – A, C, G, or T – equals 750 MB) encode not just the basic biochemical operation of cells, but also cell division (Christmas light spaghetti ball separates into 23 chromosome pairs and is pulled apart… How?), then all the detailed anatomy of differentiated cells on all those posters, plus higher-order effects such as neurological development, and then behavior? I mean, WTF?! And every cell has the same DNA, yet the same instructions somehow produce completely different structures of cells that do completely different things in different parts of the body. And when some species gains a new feature, like a complex instinctive ability or an advanced brain with the capacity for language, no new chromosomes or DNA is added; the same string of base pairs gets pressed into doing novel things along with everything else it’s been doing.

I once asked an eye Dr. He gazed into the middle distance, pointed skyward, and said “God.” But we see all this incredible machinery that clearly does the work (DNA makes RNA produces string of enzymes which becomes a protein); simply invoking a God of the gaps to paper over our lack of understanding of the details is unsatisfying.

I regularly Google “how does DNA produce structure?” but the search results overwhelmingly address “what is the structure of DNA?” (i.e. its famous double helix) instead.